Not applicable.
Not applicable.
1. Field of the Invention
This invention relates generally to a guide for a tool, and more particularly relates to a guide fence for a router and other similar tools.
2. Description of the Related Art
Guide fences are used with tools such as routers and saws to guide a workpiece such as a block of wood while the workpiece is cut or otherwise worked by the tool. Typically such fences are divided into separate portions, including an in-feed fence portion and an out-feed fence portion. A tool is generally placed between the two fence portions. Work is performed on the workpiece such as trimming the workpiece by removing a surface layer. During this operation, the workpiece may move back and forth, or seesaw, as the workpiece is trimmed or cut due to the unevenness in shape between the portion of the workpiece that has already been trimmed, and the untrimmed portion. As a result, the workpiece can be pulled further into the tool, resulting in inaccurate cutting, and possible damage to the workpiece.
It is known to alter the placement of out-feed fence portions, in order to prevent this seesawing action. For example, U.S. Pat. No. 1,664,969 to Conover describes a guide fence having a wedge shape that may be moved along an angled plate using an adjusting screw located at the blunt end of the wedge in order to push the forward surface of the guide fence outwardly. U.S. Pat. No. 1,947,885 to Tautz discloses an adjustable guide fence having an adjusting screw which operates to laterally move a generally rectangular guide fence. Similar concepts are described in U.S. Pat. No. 2,104,158 to Hedgpeth, U.S. Pat. No. 4,719,951 to Woltanski, U.S. Pat. No. 4,787,614 to Givens, and U.S. Pat. No. 5,908,061 to Blichmann.
Known adjustable guide fences require careful measurement of the amount of the workpiece to be worked and careful consideration of the required position of the guide fence. Satisfying these requirements can be time consuming, and the chances of making an error in positioning can be great. For example, if the guide fence is set too far forward, it can obstruct the movement of the workpiece, whereas if it is set too far back, the problem of seesawing of the workpiece returns. Often, a user must perform an iterative series of adjustments using a test workpiece in order to insure that the guide fence is correctly positioned.
In addition, known adjustable guide fences are only held in position by the adjusting screw that is used to adjust the positioning of the fence. Over time, vibration and wear to the adjusting screw can cause the screw to loosen slightly, causing movement of the guide fence in use.
One aspect of the invention relates to a guide for a tool. The guide includes a support structure having at least one mounting surface. A fence portion is coupled to the mounting surface. An adjustment structure for positioning the fence portion at one of a plurality of predetermined distances from the mounting surface is also included. At least one coupling is included for coupling the fence portion to the mounting surface and for holding the fence portion at the predetermined distance from the mounting surface.
The adjustment structure and coupling enable the fence portion to be incrementally moved to a predetermined distance from the mounting surface, and to be firmly held in position. The guide can thus be easily set, and is reliable in use.
Another aspect of the invention relates to a guide for a tool including a support structure having at least one mounting surface. An in-feed fence portion is coupled to the mounting surface for guiding a workpiece to the tool. An out-feed fence portion is coupled to the mounting surface for guiding the workpiece from the tool. Also included is an adjustment structure for positioning the out-feed fence portion at one of a plurality of predetermined distances from the mounting surface. A coupling structure is included for coupling the fence portions to the mounting surface and for holding the out-feed fence portion at the predetermined distance from the mounting surface.
A further aspect of the invention relates to a work table for a tool, the work table having a guide fence including a support structure attached to the work table and having a mounting surface. An in-feed fence portion is coupled to said mounting surface for guiding a workpiece to the tool. An out-feed fence portion is coupled to the mounting surface for guiding a workpiece from the tool. An adjustment structure is included for positioning the out-feed fence portion at one of a plurality of predetermined distances from the mounting surface. Coupling structures are provided for coupling the fence portions to the mounting surface and for holding the out-feed fence portion at the predetermined distance from the mounting surface.
Another aspect of the invention relates to an adjustment structure for a guide for a tool, the guide having a mounting surface and a fence portion. The adjustment structure includes an adjustment block for insertion between the mounting surface and the fence portion. The adjustment block has adjustment structure for positioning the fence portion at one of a plurality of predetermined distances from the mounting surface.
Yet a further aspect of the invention relates to a method of guiding a workpiece from a tool, including providing a support structure and having a mounting surface. A fence portion is coupled to the mounting surface for guiding a workpiece from the tool. An adjustment structure is set in order to position the fence portion at one of a plurality of predetermined distances from the remounting surface. The fence portion is held at the predetermined distance from the mounting surface.